Buoyant key case



1966 I D. J. BROUGHTON 3,

BUOYANT KEY CASE Filed Dec. 15, 1965 2 Sheets-Sheet 1 INVENTOR.

DOUGLAS 1 BROUGHTON BY 41d Dec. 20, 1966 D. J. BROUGHTON BUOYANT KEYCASE 2 Sheets-Sheet 2 Filed. Dec. 15, 1965 INVENTOR. DOUGLAS l.EIROUGHTON BY t 1 -41. 4 meal Custom United States Patent M 3,292,680BUOYANT KEY CASE Douglas J. Broughton, Springfield, Mass., assignontoBuxton, Incorporated, Agawam, Mass., a corporation of MassachusettsFiled Dec. 15, 1965. Ser. No. 514,064 6 Claims. (Cl. 150-40) Thisinvention relates to key cases, in particular buoyant key cases.

In recent years outdoor activities have rapidly increased in popularityand in ever increasing numbers people have turned to water sports as aprime source of enjoyment. For example, there are millions of peopleevery year who enjoy boating in one form or another, and, of course,fishing as well as other water sports.

Water sportsmen, like most other people, are usually burdened with keysfor various purposes, such as car keys, boat keys, house keys, etc. Intodays highly mobile population, the water sportsman usually drives hiscar to and from the water where he engages in his recreation. If duringthe day, he accidentally loses his keys in the water, it means a greatdeal of time and effort in attempting to locate and retrieve the keyswith the likelihood being failure. The loss of the keys means that thesportsman is faced with the unpleasant situation of a locked car and/ora locked house. With this in mind, I have developed a light, compact andflexible buoyant key case for use by water sportsmen.

Therefore, an object of this invention is to provide a key case whichwhen filled with a full complement of keys will float in water.

Another object is to provide a key case buoyant in nature and of suchconstructional characteristics as to be easily fabricated andmanufactured.

A further object of this invention is to provide a key case as describedabove that is not only buoyant, but also pleasing in appearance and ofconvenient size so as to be easily carried about.

A still further object of this invention is to provide a buoyant keycase as described above that is flexible, compact and comfortable, forpocket carrying in the same manner as the user would carry a non-buoyantkey case.

Other objects and advantages of this invention will become more apparentfrom the following description, which is to be considered together withthe accompanying drawings, in which:

FIG. 1 is a perspective view of a key case embodying this invention witha section broken away;

FIG. 2 is a top view of the case as shown in FIG. 1;

FIG. 3 is a perspective view of the case while open with sections brokenaway;

FIG. 4 is a plan view of the case in open condition and with the linercut away to show the constructional characteristics of the case;

FIG. 5 is a plan view similar to FIG. 4; and

FIG. 6 is a sectional view substantially on line 6-6 of FIG. 5.

Referring to the drawings, 10 designates the key ease generally. InFIGS. 1, 2, and 3 it will be clearly noted that the case is comprised ofa back portion 12 with right and left closure flaps 14 and 16respectively hinged to the side edges of the back portion 12. As shown,the right or outer closure flap 14 carries the socket 18 of a snapfastener assembly 20, while the left closure flap carries the post (notshown) of the fastener assembly 20.

A flap 22 is provided in hinged relation to the back portion 12 of thekey case 10. On this flap is carried key retaining means 24 whichsupports key loops 26 for keys, such as shown at 28.

3,292,680 Patented Dec. 20, 1966 The key case 10 is composed of threesheets, a cover sheet 30, a liner sheet 32 and a unitary sheet ofunicellular buoyant material 34 disposed between the cover and linersheets.

It will be noticed, that the cover sheet 30 and the liner sheet 32 areboth unitary sheets and that upon fabrication together with the buoyantsheet 34, they form the back portion 12 and the right and left closureflaps 14 and 16 respectively of the key case 10.

The hinging action between the back portion 12 and the closure flaps 14and 16 is secured by the flexible character of the material and by linesof fold 35 formed by the action of a sealing die through hingingsections 36 and 38 of the key case 10, as seen in FIGS. 1, 3, and 5.

The material used for the cover sheet 30 and the liner sheet 32 shouldbe soft, pliable or flexible, and preferably water impervious, such as asynthetic plastic sheet material, for example, a vinyl compound or thelike. For maximum buoyancy and ease of closing the assembled key case,it has been found that the cover 30 should have a gauge thickness offrom about .012 inch to .015 inch, while the liner 32 should be somewhatthinner with .a gauge thickness of about .008 inch to .012 inch. A goodcombination is the cover at .015 inch thickness with the liner at .012inch.

In order to impart the buoyant character to the key case, the sheet ofcellular buoyant material 34 is disposed between the cover 30 and theliner 32 before the two are joined together. The unicellular sheet 34 ispreferably soft and pliable, and when combined with the sheets 30 and 32provides a padded or cushion effect, but is of sufficient stiffness togive good form to the case. It will be observed in FIG. 4, that thesheet 34 is of one piece construction with the cutouts 40, 42 and 44being cut away to accommodate the hinging action of the case itself andthe key case snap fastener 20 respectively.

As shown in FIG. 4, the cutout sections 40 and 42 terminate inwardly ofthe upper and lower edges of the buoyant sheet 34, leaving bridgingsections 46. The bridging sections 46 permit ease of assembly of thesheet of buoyant material 34 with the cover sheet 30 and the liner sheet32, while the cutouts 40 and 42, which register with the hingingsections 36 and 38, allow the cover sheet 30 and the liner sheet 32 tobe sealed together to form the hinged relation between the back portion12 and the closure flaps 14 and 16 of the key case 10.

Even though the actual size of the key case is not limited in thisinvention, it is dependent in part upon the volume of the buoyantmaterial that must be used to float support a specific number of keys.

In the particular key case shown in the drawings, wherein the key casecomprises a cover 30 and a liner 32. a snap fastener assembly 20, a keyretaining means 24 and six standard uncut keys, the total weight thatneeds to be float supported is generally from about 68 to 74 drams. Ihave found that approximately 4.0 cubic inches of a buoyant materialwith a buoyancy factor of 55 to pounds/cu. ft. is required to floatsupport the above described case in Water.

Therefore, the volume of buoyant material to be used must be capable offloat supporting a specific number of keys depending on key case designand in turn the key case volume may be adjusted accordingly toaccommodate such a volume of buoyant material. This amount of buoyantmaterial will hereinafter be referred to as a float supporting amount.

In accordance with this invention, I have found that for purposes ofgeneral appearance and convenience of size, the float supporting amountof buoyant material should be in sheet form, preferably unitary, with athickness of from about /8 to inch, preferably about inch.

With this as the case, the volume involved in relation to floatsupporting amounts of buoyant materials may be adjusted by changing thelength and width of the buoyant material and, of course, adjusting thedimensions of the cover and liner accordingly. However, to some extentthe width and length of the key case also have limits. This limitationis controlled by practicability of design. In other words, for practicalpurposes of carrying the key case about, it must fit comfortably in theusual size clothes pocket.

As to the buoyant material itself, it may be any one of a number ofunicellular foam materials, such as polyethylene, polystyrene,polyurethane, etc. In the preferred embodiment of this invention, aflexible polyethylene foam manufactured under the trade name Ethafoam bythe Dow Chemical Company, Midland, Michigan, is used. Ethafoam has adensity of about 2.0 pounds/ft. and a buoyancy factor of more than 55pounds/ft. This This along with a water absorption of less than 1.0% byvolume makes it an ideal material for application in this invention.

As is clear, the primary purpose of the buoyant material is to floatsupport the key case and keys disposed therein. However, there is asecondary purpose which should be kept in mind when choosing the buoyantmaterial. The material must not only act as buoyant matter, but mustalso act as a stiffener for the various compartments of the key case.Yet, there must be a balance between its stiffening properties and itsflexibility properties, otherwise the key case will not be suitable tobe carried around in a clothing pocket.

The fabrication of the buoyant key case is simple and efficient. Inessence, the liner sheet 32 is placed with its outside surface facingdownwardly. Next an adhe sive coating may be applied to one or the otheror both of the surfaces of the cellular material or liner. This isfollowed by the positioning of the unitary sheet of the cellularmaterial 34 on the liner 32 to which itadheres. This step is used toalign the buoyant material 34 between the liner sheet 32 and the coversheet 30 so as to permit proper heat sealing of the two sheets withoutadversely affecting the buoyant material 34.

After the buoyant cellular material 34 is disposed on the liner sheet32, the cover sheet 30 is placed over same, and the two sheets aresealed together by appropriate means, such as heat sealing or cementing,about the perimeter of the key case and along the lines of fold 35through the hinging sections 36 and 38. In the sealing operation, caremust be taken not to crush the cellular foam material as this willadversely affect its buoyancy properties by driving out pocketed air.With this problem in mind, the cover sheet 30 and liner sheet 32 arepurposely made oversize as compared to the cellular sheet material,thereby leaving a free edge for sealing purposes, see FIG. 4.

Once the sealing operation is completed, the key case itself is awater-tight chamber. As the unicellular foam used accommodatesessentially all space between the cover sheet 30 and the liner sheet32,'should either cover or liner sheet be perforated the amount of wateradmitted by the perforation will not substantially affect the buoyancyof the key case as unicellular foams have a very low water absorptioncapacity as well as very low capillarity.

Finally, upon the complete sealing of the cover 30 to the liner 32, theflap 22 is provided in hinged connection with the back member 12 of thekey case 10 with suitable means 24 for supporting keys 28. In general,the flap 22 is of two piece construction, the first piece being a rigidbody upon which is superimposed a vinyl covering with a gauge thicknessof about .012 to .015 inch. These two parts are sealed together and inturn both are hinge sealed to the back member 12 of the key case 10.

The key supporting mean-s 24 which is attached to the flap 22 may takeany desired form, that shown being more fully disclosed in the patent toHarvey No. 2,582,037 issued on January 8, 1952. Preferably, the keysupporting means 24 includes a rigid bar member extending transverselyof the case, such means being provided, in the key supporting meansshown, by the metal cylinder 48 to which the individual key retainingloops 26 are attached.

Although the invention has been particularly shown and described, hiscontemplated that various changes and modifications may be made withoutdeparting from the scope thereof as indicated by the following claims.

Having thus described the invention, what is claimed is: 1. A buoyantkey case comprising a pair of unitary moisture impervious sheets, aunitary sheet of unicellular buoyant material disposed between saidmoisture im-' closure flaps comprisinga unitary moisture impervious 7cover sheet, a unitary moisture impervious liner sheet, said cover sheethaving a thickness greater than the thickness of said liner sheet, aunitary sheet of unicellular buoyant material with cut-outs thereindisposed between said cover sheet and said liner sheet and key retainingmeans disposed on the back member of said key case,

said cover sheet and said liner sheet being sealed together about theirperiphery forming at least one water-tight compartment and also beingsealed together through said cut-outs thereby forming hinges betweensaid back mem-.

her and closure flaps.

3. Buoyant key case as set forth in claim 2 wherein the thickness of thecover sheet is from about .012 inch to .015 inch and the thickness ofsaid liner sheet is from.

about .008 inch to .012 inch.

4. Buoyant key case as set forth in claim 3 wherein said unitary'sheetof unicellular buoyant material is a polyethylene foam, and said coverand liner sheets are sheet vinyl plastic.

5. Buoyant key case as set forth in claim 4 in which said cut-outs aredisposed in spaced parallel relation perpendicular to the upper andlower edges of said case,

said cut-outs terminating inwardly of said upper and lower edges toleave bridging portions interconnecting the portions of said unicellularsheet within the back member and closure flaps of said case.

6.- Buoyant key case comprising a unitary moisture impervious vinylcover including a back member with closure flaps hinged to the sideedges thereof, a unitary moisture impervious vinyl liner including aback member with closure flaps hinged to the side edges thereof, key

retaining means disposed in saidkey case, a float supporting amount ofa' unicellular buoyant sheet material sealed between said cover and saidliner sheet, said amount being capable of float supporting said key casewith a full complement of keys disposed on said key retaining means.

References Cited by the Examiner UNITED STATES PATENTS 2,051,432 8/1936Zahn 40 2,661,785 12/1953 Daust 150-28 2,667,198 1/1954 Klein 150 2.12,795,258 6/1957 Berry et al. 150-28 2,837,132 6/1958 Daust 150--28FRANKLIN T. GARRETT, Primary Examiner.

1. A BUOYANT KEY CASE COMPRISING A PAIR OF UNITARY MOISTURE IMPERVIOUSSHEETS, A UNITARY SHEET OF UNICELLULAR BUOYANT MATERIAL DISPOSED BETWEENSAID MOISTURE IMPERVIOUS SHEETS AND HAVING CUT-OUTS THEREIN, KEYRETAINING MEANS DISPOSED IN SAID KEY CASE, SAID MOISTURE IMPERVIOUSSHEETS BEING SEALED TOGETHER ABOUAT THEIR PERIPHERY FORMING AT LEAST ONEWATER-TIGHT COMPARTMENT AND ALSO BEING SEALED TOGETHER THROUGH SAIDCUT-OUTS IN SAID SHEET OF BUOYANT MATERIAL FORMING HINGED CLOSURE FLAPS.